It is critical to rigorously determine the mechanical properties of granitic rocks to effectively analyze and manage subsurface engineering activities, such as geothermal energy exploitation and nuclear waste disposal. However, the required deep drilling and sampling for macroscale rock mechanics experiments (macro-RME) are challenging and expensive. In this study, we developed a novel accurate grain-based modeling (AGBM) using the results of microscale rock mechanics experiments (micro-RME) to determine the elastic properties of arbitrarily shaped granite. The microstructure of each sample and Young's modulus of rock-forming minerals were measured with a TESCAN Integrated Mineral Analyzer (TIMA) and nanoindentation test. The geometry and Young's modulus of interphases between different minerals were determined using an advanced algorithm with atomic force microscopy (AFM) test. With the microstructure and microscale mechanical properties obtained from the micro-RME, the AGBM was applied to derive the macroscale mechanical properties of the granite samples. This new methodology was demonstrated on small test specimens extracted from granite fragments. Because we can use test specimens from arbitrarily shaped and small rock fragments, this new methodology has been proven to be a breakthrough from the conventional technology of macro-RME.

严格确定花岗岩的力学特性对于有效分析和管理地下工程活动（例如地热能开发和核废料处理）至关重要。然而，宏观岩石力学实验 (macro-RME) 所需的深钻和取样具有挑战性且成本高昂。在这项研究中，我们利用微尺度岩石力学实验 (micro-RME) 的结果开发了一种新的基于颗粒的精确建模 (AGBM)，以确定任意形状花岗岩的弹性特性。使用 TESCAN 综合矿物分析仪 (TIMA) 和纳米压痕测试测量每个样品的微观结构和成岩矿物的杨氏模量. 使用原子力显微镜 (AFM) 测试的先进算法确定不同矿物之间界面的几何形状和杨氏模量。利用从微观RME获得的微观结构和微观力学性能，应用AGBM来推导花岗岩样品的宏观力学性能。这种新方法在从花岗岩碎片中提取的小试样上得到了证明。由于我们可以使用任意形状和小岩石碎片的试样，这种新方法已被证明是对传统宏观 RME 技术的突破。